Hermetically sealed terminal structure



Jan. 26, 1965 H. F. MASON HERMETICALLY SEALED TERMINAL STRUCTURE FiledApril l0, 1961 United States Patent O M' 3,157,608 nera/rarissimi(snALEn TERMINAL STRUCTURE Howard l?. Mason, Los Angeles, Caiif.,assigner to Ansul Chemical Qompany, a corporation of Wisconsin FiledApr. 1t), 1961, Ser. No. 1631,77il 2 Claims. (Cl. 174-505@ The presentinvention relates in general to a terminal structure, such as anelectrical terminal structure, and, more particularly, to a terminalstructure which is hermetically sealed.

General objects of the invention are to provide a hermetically sealedterminal structure which permits the use of low resistance terminalmaterials, which is not adversely affected by thermal expansion andcontraction of the terminals even with terminal materials having highcochicients of thermal expansion, and which will remain hermeticallysealed despite severe thermal shock, mechanical shock, torqueapplications, and the like.

rhe foregoing objects are attainable by providing, and an importantobject of the invention is to provide, a hermetically sealed terminalstructure which includes a laminated wall comprising preformed, rigidlaminae having communicating holes with nonaligned edges, and a terminalhaving portions respectively complementary to and disposed in suchholes, the laminae being bonded together with the terminal in place.

With the foregoing construction, the terminal and the laminated wall aresecurely locked together mechanically even when the terminal structureis subjected to severe thermal shock, mechanical shock, torqueapplications, or the like, and there is an irregular, stepped interfacebetween the laminated wall and the terminal to virtually eliminate anypossibility of leakage along such interface.

Other objects are to provide a terminal structure of the foregoingnature wherein the irregular, stepped interface between the laminatedwall and the terminal is formed by varying the lateral configuration ofthe terminal longitudinally thereof and using complementary holes in thelaminae having different shapes and/ or sizes and/ or angularorientations and/ or the like.

The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults thereof which will be evident to those skilled in thehermetically sealed terminal structure art in the light of thisdisclosure, may be achieved with the exemplary embodiments of theinvention described in detail hereinafter and illustrated in theaccompanying drawing, in which:

FlG. l is a fragmentary plan View illustrative of a terminal structurewhich embodies the invention;

FIG. 2 is a sectional view taken along the irregular arrowed line 2-2 ofFIG. l;

FIG. 3 is an exploded perspective View of a laminated Wall of theterminal structure of the invention;

FlGS. 4 and 5 are perspective views of terminals of the terminalstructure of the invention; and

FIG. 6 is a perspective View showing the terminals of FlGS. 4 and 5, andother similar terminals, assembled with certain of the laminae of thelaminated wall of FG. 3 of the drawing.

ln the drawing, the hermetically sealed terminal structure of theinvention is designated generally by the numeral llt) and includes alaminated wall 12 through which extend terminals 14, terminals 16 andterminals 18. As will be explained, these terminals are anchored in thelaminated wall 12, the laminae of such Wall being bonded together tosecure the terminals in place.

As hereinbefore outlined, and as will be discussed in more detailhereinafter, there are irregular, stepped inter- Patented Jan. 26, 1965lCe faces between the laminated wall 12 and the terminals 14, 16 and 18so as to virtually eliminate any possibility of leakage along suchinterfaces. The irregular, stepped interface between the laminated wall12 and each of the terminals 14, 16 and 18 is formed by providing holesin the laminae of the laminated wall which have different shapes and/orsizes and/or angular orientations and/or the like, and bycomplementarily varying the cross sectional configuration of theterminal longitudinally thereof so that each longitudinal increment ofthe terminal tits snugly in a corresponding hole.

The laminated wall 12 includes, as a main supporting lamina 2@ thereof,one wall of a housing 22. The latter is preferably formed of sheetmetal.

Considering one of the terminals 14 and its relationship to thelaminated wall 12, each terminal 14, as best shown in FIG. 4 of thedrawing, comprises a stud having an externally threaded outer end 24adapted to accommodate a nut 26. The terminal 14 is providedintermediate its ends with a square head 28 and is provided at its innerend with a rectangular projection 30 having a hole 32 therethrough inwhich an electrical conductor, not shown, may be soldered.

The portion of the laminated wall 12 associated with each terminal 14comprises stacked laminae 34, 36, 38, 4d and 42, of electricalinsulating material, which are all bonded together and the lamina 42 ofwhich is preferably bonded to the main supporting lamina 20. The lamina34 is provided therein with a rectangular hole 44 complementary to andreceiving the rectangular projection 3l) on the terminal 14 underconsideration. The laminae 36, 3d and 4@ are respectively provided withholes 46, 4S and 5@ complementary to and receiving therein the squarehead 28 of the terminal 14. Similarly, the lamina 42 is providedtherethrough with a round hole complementary to and receiving thereinthe cylindrical portion of the terminal 14 which is located outwardly ofthe square head 28.

It will be noted that the hole 44 differs in size and shape from theholes 46, 48 and Sil, and that the latter differ in size and shape fromthe hole 52. This provides an irregular, stepped interface between theterminal 14 and the laminae 34, 36, 38, 4t) and 42 to avoid any directleakage path between the terminal and such laminae even if there is nota perfect bond between the terminal and the laminae in question. It willbe understood that while the terminal 14 has been shown as provided withrectangular, square and circular portions in the correspondingrectangular, square and circular holes, other shapes and otherrelationships may be used to obtain the desired irregular, steppedinterface between the terminal and the laminae 34, 36, 38, 40 and 42.

The cylindrical portion of the terminal 14 projects outwardly through ahole 54 in the main supporting lamina 26 and is surrounded by aninsulating bushing 56 having a reduced-diameter portion fitting tightlyin the hole 54. Outwardly of the bushing 56 are washers 58 and 60 andthe nut 26, the washers being adapted to receive a terminal cliptherebetween and at least the washer 58 preferably being formed of anelectrically conductive material, As will be apparent, the laminae 20and 42, the bushing S6 and the washers 58 and 60 are all clamped betweenthe nut 26 and the square head 28 of the terminal 14.

Outwardly of the main supporting lamina 20 is an outer lamina 62 havingtherein a hole 64 which accommodates the bushing 56. This outer laminamay be provided with terminal-identifying indicia thereon.

Prior to assembly, the various laminae 34, 36, 38, 40 and 42 are coatedon both sides with a curable bonding agent, such as a synthetic resin,and are assembled with sideration in place within the laminated wall.

a the terminal 14. The structure just described is then assembled withthe housing 22, the bushing 26 and the washers S and 6). The entireassembly is then clamped together with the nut 26. Preferably, theportions of the bushing 56 in contact with the housing 22 and the lamina42 are also coated with a curable bonding agent. The bonding agent isthen caused to cure, with the result that the coated components arepermanently hermetically sealed together. The outer lamina 62 may beapplied during assembly of the components just discussed, orsubsequently.

With thin laminae as shown, the laminae 34, 36, 38 and 4t? are securedduring clamp up by friction with the terminal 14 and/ or by the bondingagent. Consequently, the terminal 14 and its nut 26 provide the onlyclamping means needed. With heavier laminae, however, it may benecessary to clamp up the laminae 34, 36, 38 and it? separately.

The resulting terminal structure is tightly sealed and sturdy andpositively locks the terminal 14 under con- The hermetio seal and themechanical interlock between the laminated wall 12 and the terminal 14retain their integrity despite severe thermal shock, mechanical shock,torque applications, and the like, even when terminal materials havinghigh coeiricients of thermal expansion are used. Also, as previouslypointed out, the irregular, stepped interface between the laminated wall12 and the terminal i4 virtually eliminates any possibility of leakagesince there is no direct leakage path through the terminal structure.

The remaining terminals 14 and 16 have the same relationship to thelaminated wall 1.2, and are assembled therewith in the same manner, asthe terminal 14 just described. The terminals 16 differ only in beingsomewhat larger and longer, the structural differences required in thelaminated wall l2 to accommodate same being apparent so that any furtherdescription is not necessary.

The terminals 18, which are designed to have soldered connections atboth ends, have substantially the same relationship to the laminatedwall l2 as the terminals 14 and 16, and are assembled therewith in asimilar manner. Consequently, only a brief description of one of theterminals 18 and its relationship to the laminated wall 12 is necessary.

As best shown in FIG. 5 of the drawing, each terminal 18 is ofrectangular cross section and includes a substantially square head 66intermediate its ends. inwardly ot the head 66 is a lamina 63, ofinsulating material, having a rectangular hole itl therethrough for theterminal 13. The lamina 68 is disposed between the laminae 3S and 40,the lamina 38 having a recess 72 in one edge thereof to receive acorresponding edge of the lamina 63.

The square head do of each terminal 1S lits into a cornplementary hole74 in the lamina 4l?. Outwardly of the head 66, each terminal 13 extendsthrough a rectangular hole 76 in the lamina 42. The terminals h3 projectoutwardly through, and lit tightly in, holes 78 in a lamina Sti ofinsulating material which is disposed in an opening 82 Vin the mainsupporting lamina Ztl and which underlies, and is covered by, the outerlamina 62. As previously pointed out, the terminals TLS are assembledand sealed with respect to the corresponding laminae in thesarne manneras the terminals 14 and 16.

Although exemplary embodiments of the invention have been disclosedherein for purposes oi illustration, it

will be understood that various changes, modifications and substitutionsmay be incorporated in such embodiments without departing from thespirit of the invention as dened by the claims which follow.

I claim:

l. ln a hermetically sealed terminal structure, the

combination of:

(a) a laminated wall comprising preformed rigid laminae of electricalinsulating material having communicating holes therethrough;

{,5) certain of said holes having edges which are nonaligned relative toeach other;

(c) at least one of said holes being noncircular;

(d) a terminal extending through said wall and having portionsrespectively complementary to and disposed in certain of said holes withnonaligned edges and said noncircular hole;

(e) an outer lamina oi said wall having a hole therethrough which islarged than said terminal;

(f) a bushing of electrical insulating material encompassing saidterminal and disposed in and complementary to said hole in said outerlamina;

(g) said laminae and said bushing being bonded together; and

(h) whereby to hermetically seal said terminal in said laminated walland said bushing with a stepped, `sealed interface between said terminaland said laminated wall to positively prevent leake through saidlaminated wall along the exterior of said terminal.

2. In a hermetically sealed terminal structure, the

combination of (a) a laminated wall comprising preformed rigid laminatehaving communicating holes therethrough;

(b) certain oi said holes having edges which are nonaligned relative toeach other;

(c) at least one ot said holes being noncircular;

(d) a terminal extending through said wall and having portionsrespectively complementary to and disposed in certain of said holes withnonaligned edges and said noncircular hole;

(e) at least one lamina of said wall having a hole therethrough which islarger than said terminal;

(f) a bushing encompassing said terminal and disposed in andcomplementary to said hole in said one lamina;

g) said laminae and said bushing being bonded together;

(It) whereby to hermetically seal said terminal in said laminated walland said bushing with a stepped, sealed interface between said terminaland said laminated wall to positively prevent leakage through saidlaminated wall along the exterior of said terminal; and

(i) said one lamina being formed of sheet metal and the remainder ofsaid laminae and said bushing being formed of electrical insulatingmaterial.

References tCited in the tile of this patent UNTED STATES ATENTS1,883,663 Fitz Gerald Oct. 18, 1932 1,962,487 Douglas lune l2, 19342,388,054 Hartzell Oct. 30, 1945 2,623,101 Kurland et al. Dec. 23, 19522,678,960 Iensen May lS, 1954

1. IN A HERMETICALLY SEALED TERMINAL STRUCTURE, THE COMBINATION OF: (A)A LAMINATED WALL COMPRISING PREFORMED RIGID LAMINAE OF ELECTRICALINSULATING MATERIAL HAVING COMMUNICATING HOLES THERETHROUGH; (B) CERTAINOF SAID HOLES HAVING EDGES WHICH ARE NONALIGNED RELATIVE TO EACH OTHER;(C) AT LEAST ONE OF SAID HOLES BEING NONCIRCULAR; (D) A TERMINALEXTENDING THROUGH SAID WALL AND HAVING PORTIONS RESPECTIVELYCOMPLEMENTARY TO AND DISPOSED IN CERTAIN OF SAID HOLES WITH NONALIGNEDEDGES AND SAID NONCIRCULAR HOLE; (E) AN OUTER LAMINA OF SAID WALL HAVINGA HOLE THERETHROUGH WHICH IS LARGED THAN SAID TERMINAL;